Phytic acid (PA) is a naturallu occurring polyphosphorylated carbohydrate that is present in substantial amounts in almost all plants and mammalian cells. Recently PA has received much attention for its role in anticancer activity. We investigated the preventive effect of PA on the formation of colonic aberrant crypt foci (ACF), a preneoplastic lesion, induced by azoxymethane (AOM). After acclimation for one week, six-week old male ICR mice were fed on the AIN-93G purified diet and PA (0.5% or 2% PA in water) for 8 weeks. The animals were treated with azoxymethane (AOM, 10 mg/kg b.w.) three times (0, 1, and 2 weeks) to induce colonic aberrant crypt foci (ACF). After sacrifice, the total numbers of aberrant crypts (AC) and ACF in colonic mucosa were counted after staining with methylene blue. Blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. AOM treatment without PA induced the total numbers of 85.7 ± 12.9 and 115.2 ± 19.9, respectively. PA at the dose of 2% AC/colon by PA at the dose of 0.5% were 73.4 ± 12.9 and 115.2 ± 19.9, respectively. PA at the dose of 2% significantly decreased the ACF and AC numbers to 56.5 ± 14.6 and 95.4 ± 17.2, respectively (p＜0.01). PA at the doses of 0.5 and 2% decreased the numbers of ACF and AC/colon in a dose-dependent manner. Although some parameters in blood counts and serum chemistry were changed compared with the control, no specific toxicity was found. Theses findings suggest that phytic acid can be a chemopreventive agent for colon carcinogenesis resulting from inhibition of the development of ACF in ICR mice.

The purpose of this study was to examine the effects of vi tamin D3 and 1'etinoic acid(RA) on the human mesenchymal stem ce!ls(MSC) g1'owth and osteogenic differentiations. Cell proliferation, mineralization, cell cycle, expression of cell cycle regu l atOJγ proteins and markers fo1' osteogenic differenatiaiton were determined by MTI assay, mineralization assay, flow cytomet1'Y‘ and Western blot analysis, respectively. Cell viability was dec1'ease by each vitamin D3 and RA added to MSC. it was more decrease by vitamin D3 and RA. Mineralized nodule formation revealed similar expression pattern with positive cont rol group at vitamin D3 and RA mixed add to MSC. At vitamin D3 and RA mixed add to MSC after 7 days of incubation was increase G1 s tage. after 21 days of incubation was inhibit cell cycle prog1'ess by inc1'ease of sub-G1 Treatment vitamin D3 to MSC inhibits p53 and p21, but inc1'ease pRb. RA inhibit p53, but increase p21 and pRb, vitamin D3 plus RA group was same as added RA group. so two vitamin was effect to inhibited cell growth each different mechanism. Expression of BMP-2 protein was prominent in osteogonic supplement treated g1'oup of MSC at 2 weeks cultivation days, but vi tamin D3 treatment decreased BMP-2 expression rather than in (+) control group. BSP protein was notably increased in the OS compa red to positive controls at 2 weeks cultivation, but similar to that of vitamin D3 group t1'eatment group and was least expressed in plus RA mixed group, at 3 weeks, BSP expression was similar to 1'esult of 2 weeks Collectively, these results shows that vitamin D3 and RA have diffe1'ential effects on the MSCs g1'owth and differ entia tion 211

We have examined the effect of NO donor, S-nitl‘ oso-N-acetyl-DL-penicillamine(SNAP) on heme oxygenase-1 (HQ-l) ex pression in human oral immortalized & malignant keratinocytes, and investigated in the control of keratinocyte proliferation evidence tha t HO-1 cou ld be involved in a low dose of NO, NO inhibitor, HOinducer, and HO inhibitor medi ated cytoprotect ion against cytotoxi city induced by a high dose of NO Oral keratinocyte growth inhibitory or anti-proliferative effects were exerted by with SNAP and hemin in a dose- and cul tivation time dependent manner The level of HQ-1 protein was increased in all cell types after exposure hernin dose, and the hemin induced HQ-1 protein achieved at higher maximum level by 12 hrs in all kind of cells , The pretreatment of cells with 0, 2 μ M SNAP reduced 1 mM SNAP-induced death in IHOK and HN4 cells , These cytoprotective effects on high dose of NO induced HQ-1 expresion and cell ular toxicity were blocked by low dose of SNAP, HCB, and ZnPP IX supporting the involvement of HQ-1 in high dose NO induced growth arrest or cell death, But these cytoprotection pattern is different from immortalized and malignant keratinocytes , These results indirectly demonstrate that HQ-1 could be involved in cytoprotection by NO priming against high dose NO induced cytotoxicity in immortalized and maigla nt oral keratinocytes, Thus, HQ-1 might be an important cellular target of NO donor, with clinical implications for the pre vention of inJlammatory di seases and anti-tumor immunity

Insulin-like growth factor II (IGF2) and H19 genes are mutually imprinted genes which may be responsible for abnormalities in the cloned fetuses and offspring. This study was performed to identify putative differentially methylated regions (DMRs) of porcine H19 locus and to explore its genomic imprinting in in vitro fertilized (IVF) and somatic cell nuclear transferred (SCNT) embryos. Based on mice genomic data, we identified DMRs on H19 and found porcine H19 DMRs that included three CTCF binding sites. Methylation patterns in IVF and SCNT embryos at the 2-, 4-, 8～16-cells and blastocyst stages were analyzed by BS (Bisulfite Sequencing)-PCR. The CpGs in CTCF1 was significantly unmethylated in the 2-cell stage IVF embryos. However, the 4- (29.1%) and 8～16-cell (68.2%) and blastocyst (48.2%) stages showed higher methylation levels (p<0.01). On the other hand, SCNT embryos were unmethylayted (0～2%) at all stages of development. The CpGs in CTCF2 showed almost unmethylation levels at the 2-, 4- and 8～16-cell and blastocyst stages of development in both IVF (0～14.1%) and SCNT (0～6.4%) embryos. At all stages of development, CTCF3 was unmethylated in IVF (0～17.3%) and SCNT (0～1.2%) embryos except at the blastocyst stage (54.5%) of IVF embryos. In conclusion, porcine SCNT embryos showed an aberrant methylation pattern comprised to IVF embryos. Therefore, we suggest that the aberrant methylation pattern of H19 loci may be a reason for increased abnormal fetus after embryo transfer of porcine SCNT embryos.